1. Field of the Invention
This invention relates generally to television receivers and, more particularly, is directed to a picture-within-a picture-type television receiver incorporating a video cassette recorder.
2. Description of the Prior Art
Generally, a video cassette recorder (VCR) having a tuner circuit for selecting a channel and a television receiver are constructed independently of each other. When in use, the VCR and television receiver are connected so that a program on a desired channel may be recorded by the VCR while such program is also being displayed on the picture screen of the television receiver, or so that a program on one channel can be recorded while a program on a different channel is displayed on the picture screen. Since the VCR and the television receiver are constructed independently of each other, the user rarely confuses the channel selection section of the VCR with the channel selection section of the television receiver. Accordingly, the user is not likely to confuse the channel of the program to be received and displayed by the television receiver and the channel of the program to be recorded on the VCR. Thus, the operations for reproducing or displaying and for recording the desired television programs can be readily controlled.
When the so-called deck type VCR, which does not have an independent tuner circuit, and a television receiver are combined as a unitary structure, such unitary or combined structure is provided with only a single tuner circuit, and the program on the channel being displayed by the picture screen can be recorded by the VCR in response to the mere actuation of a recording switch, for example, as disclosed in Japanese Published Pat. Application No. 61-11510. Such arrangement has the virtue of being operationally simple, but it suffers the disadvantage of permitting recording of only the program that is being displayed on the picture screen.
It has further been proposed to provide a so-called split-screen or picture-within-a picture type television receiver in which a sub-channel picture is superimposed on, or displayed as an inset within a main-channel picture. When such split-screen television receiver is combined with the previously mentioned deck-type VCR, the combined apparatus is provided with a tuner circuit for the main-channel picture and a tuner circuit for the sub-channel picture. If such combined apparatus is arranged so that the video signal corresponding to the main-channel picture is recorded by the VCR upon actuation of a recording switch, the operation of the combined apparatus is facilitated, but the VCR integrated with the split-screen television receiver can not record a program broadcast on a channel different from that on which the main-channel picture appears. In other words, the VCR integrated with the split-screen television receiver can not record a video signal corresponding to the sub-channel picture while the main-channel picture is displayed on the screen of the television receiver.
In order to avoid the above defect, the combination of a split-screen television receiver with a VCR has been modified so that the VCR records the video signal corresponding to the sub-channel picture whenever a recording switch is actuated. In this modified combined apparatus, the main-channel picture corresponding to the program on one channel can be displayed on the screen of the television receiver while the VCR records a program on a different channel, that is, the channel providing the sub-channel picture. However, in the split-screen television receiver, the sub-channel picture is only displayed in response to a respective control signal provided at the will of the user. Therefore, if such control signal has not been provided for display of the sub-channel picture, the program being recorded can not be readily monitored or confirmed.
It is also known to provide a split-screen or picture-within-a picture type television receiver incorporating a VCR with a switch or control for selecting either the video signal corresponding to main-channel picture or the video signal corresponding to the sub-channel picture to be recorded by the VCR. However, here again, since the sub-channel picture is not always displayed, the content of the program being recorded can not be always monitored or confirmed with any degree of certainty. Moreover, when the split-screen television receiver and VCR are combined in a unitary structure or common cabinet and the various operation controlling switches are all provided at the front panel of such cabinet, the user is likely to become confused as to the correspondence between the program being recorded and the program forming the main-channel picture and/or the sub-channel picture.
In an attempt to avoid such confusion, consideration has also been given to an arrangement in which, when only a main-channel picture is displayed on the screen of the television receiver, the program recorded corresponds to such main-channel picture, whereas, when the television receiver is controlled to simultaneously display a main-channel picture and a sub-channel picture, the program corresponding to the sub-channel picture is the one which is recorded. However, a split-screen television receiver having the foregoing arrangement is relatively difficult to program and operate.